Permit Meta Viewport in Html (#3623)

Fix #3565. Requester suggested adding viewport as a property of Html Writer. I think it would fit better as a Document Property, so that it can be both read and written, just like other meta properties, making it easier to load an Html spreadsheet and save it as a new one preserving this property. It is an open question whether we should try to preserve this property when writing to other spreadsheet types, e.g. as a custom property for Xlsx. For now, I am not attempting that. Requester also suggested this as a boolean property, but there are other parameters and different values that might be used for viewport. So I am defining it as a string property, with a constant SUGGESTED_VIEWPORT that can be used for requester's use case.

src/PhpSpreadsheet/Document/Properties.php

@@ -109,6 +109,8 @@ class Properties
 
     private string $hyperlinkBase = '';
 
+    private string $viewport = '';
+
     /**
      * Create a new Document Properties instance.
      */
@@ -548,4 +550,18 @@ class Properties
 
         return $this;
     }
+
+    public function getViewport(): string
+    {
+        return $this->viewport;
+    }
+
+    public const SUGGESTED_VIEWPORT = 'width=device-width, initial-scale=1';
+
+    public function setViewport(string $viewport): self
+    {
+        $this->viewport = $viewport;
+
+        return $this;
+    }
 }

src/PhpSpreadsheet/Reader/Html.php

@@ -748,6 +748,10 @@ class Html extends BaseReader
                     case 'title':
                         $properties->setTitle($metaContent);
 
+                        break;
+                    case 'viewport':
+                        $properties->setViewport($metaContent);
+
                         break;
                     default:
                         if (preg_match('/^custom[.](bool|date|float|int|string)[.](.+)$/', $metaName, $matches) === 1) {

src/PhpSpreadsheet/Writer/Html.php

@@ -385,6 +385,7 @@ class Html extends BaseWriter
         $html .= self::generateMeta($properties->getCompany(), 'company');
         $html .= self::generateMeta($properties->getManager(), 'manager');
         $html .= self::generateMeta($properties->getLastModifiedBy(), 'lastModifiedBy');
+        $html .= self::generateMeta($properties->getViewport(), 'viewport');
         $date = Date::dateTimeFromTimestamp((string) $properties->getCreated());
         $date->setTimeZone(Date::getDefaultOrLocalTimeZone());
         $html .= self::generateMeta($date->format(DATE_W3C), 'created');

tests/PhpSpreadsheetTests/Reader/Html/ViewportTest.php

@@ -0,0 +1,44 @@
+<?php
+
+namespace PhpOffice\PhpSpreadsheetTests\Reader\Html;
+
+use PhpOffice\PhpSpreadsheet\Document\Properties;
+use PhpOffice\PhpSpreadsheet\Spreadsheet;
+use PhpOffice\PhpSpreadsheetTests\Functional\AbstractFunctional;
+
+class ViewportTest extends AbstractFunctional
+{
+    public function testViewport(): void
+    {
+        $spreadsheetOld = new Spreadsheet();
+        $spreadsheetOld->getProperties()->setViewport(Properties::SUGGESTED_VIEWPORT);
+        $osheet = $spreadsheetOld->getActiveSheet();
+        $osheet->getCell('A1')->setValue(1);
+
+        $spreadsheet = $this->writeAndReload($spreadsheetOld, 'Html');
+        $spreadsheetOld->disconnectWorksheets();
+
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertSame(1, $sheet->getCell('A1')->getValue());
+        self::assertSame('width=device-width, initial-scale=1', $spreadsheet->getProperties()->getViewport());
+
+        $spreadsheet->disconnectWorksheets();
+    }
+
+    public function testNoViewport(): void
+    {
+        $spreadsheetOld = new Spreadsheet();
+        //$spreadsheetOld->getProperties()->setViewport(SUGGESTED_VIEWPORT);
+        $osheet = $spreadsheetOld->getActiveSheet();
+        $osheet->getCell('A1')->setValue(1);
+
+        $spreadsheet = $this->writeAndReload($spreadsheetOld, 'Html');
+        $spreadsheetOld->disconnectWorksheets();
+
+        $sheet = $spreadsheet->getActiveSheet();
+        self::assertSame(1, $sheet->getCell('A1')->getValue());
+        self::assertSame('', $spreadsheet->getProperties()->getViewport());
+
+        $spreadsheet->disconnectWorksheets();
+    }
+}